Table 3. The values of LRV MRI indices in the diagnosis of NCS.
| Parameters | Se (95% CI) | Sp (95% CI) | PPV (95% CI) | NPV (95% CI) | PLR (95% CI) | NLR (95% CI) | YI (%) |
|---|---|---|---|---|---|---|---|
| SMA angle <36.8a | 82.8 (0.7, 0.9) | 82.5 (0.8, 0.9) | 73.8 (0.6, 0.9) | 88.9 (0.8, 1.0) | 4.7 (3.3, 7.9) | 0.2 (0.1, 0.3) | 75.3 |
| Beak signb | 77.6 (0.7, 0.9) | 93.8 (0.9, 1.0) | 88.2 (0.8, 1.00) | 87.5 (0.8, 1.0) | 12.5 (10.6, 58.8) | 0.2 (0.1, 0.2) | 71.4 |
| CR >3.99c | 79.3 (0.7, 0.9) | 93.8 (0.9, 1.0) | 88.5 (0.8, 1.0) | 88.3 (0.8, 0.9) | 12.8 (7.1, 64.4) | 0.2 (0.1, 0.4) | 73.1 |
| a and b | 67.2 (0.6, 0.8) | 97.9 (0.9, 1.0) | 95.1 (0.9, 1.0) | 83.3 (0.8, 0.9) | 32.0 (13.9, 83.3) | 0.3 (0.2, 0.4) | 65.1 |
| a and c | 60.3 (0.5, 0.7) | 95.9 (0.9, 1.0) | 89.7 (0.8, 1.0) | 80.1 (0.7, 0.9) | 14.7 (7.5, 62.5) | 0.4 (0.3, 0.5) | 56.2 |
| b and c | 62.1 (0.5, 0.8) | 97.9 (0.9, 1.0) | 94.7 (0.8, 1.0) | 82.6 (0.8, 0.9) | 29.6 (13.0, 76.9) | 0.4 (0.3, 0.5) | 60.1 |
LRV, left renal vein; MRI, magnetic resonance imaging; SMA, superior mesenteric artery; NCS, nutcracker syndrome; Se, sensitivity; CI, confidence interval; Sp, specificity; PPV, positive predictive value; NPV, negative predictive value; PLR, positive likelihood ratio; NLR, negative likelihood ratio; YI, Youden index; CR, compression ratio. a: SMA angle <36.8; b: beak sign; c: CR >3.99.